Joint observations by Cluster satellites of bursty bulk flows in the magnetotail - Cao, JB; Ma, YD; Parks, G; Reme, H; Dandouras, I; Nakamura, R; Zhang, TL; Zong, Q; Lucek, E; Carr, CM; Liu, ZX; Zhou, GC (JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2006)